Machine tool with a tool changer



Nov. 1', 1966 F. ZANKL ET AL MACHINE TOOL WITH A TOOL CHANGER 5Sheets-Sheet 1 Original Filed Aug. 30, 1962 [I] II Nov. 1, 1966 F.,ZANKL ETAL 3,281,935

MACHINE TOOL WITH A TOOL CHANGER Original Filed Aug. 30, 1962 5Sheets-Sheet 2 INVENTOR. FRANK ZA/VKZ 4M0 Nov. 1, 1966 F. ZANKL ET AL3,281,935

MACHINE TOOL WITH A TOOL CHANGER Original Filed Aug. 30, 1962 5Sheets-Sheet 5 INVENTORS FRANK z/W/(z A'A/O Nov. 1, 1966 F. ZANKL ET ALMACHINE TOOL WITH A TOOL CHANGER 5 Sheets-Sheet 4 Original Filed Aug.30, 1962 Nov. 1, 1966 Original Filed Aug. 30, 1962 F. ZANKL ET ALMACHINE TOOL WITH A TOOL CHANGER 275 1 5 Sheets-Sheet 5 279 26/ :nfl

1'1 55x ---42 5 [E] E m, fi

INVENTORS FR/I/VK 24mm 411/0 BY 54m 2 ZOH/VE/S 3,281,935 MACHINE TUULWl'lll-l A TOOL CHANGER Frank Zanlil and Earl R. Lohneis, Milwaukee,Wis., as-

signors to Kearney 8: Trecker Corporation, West Allis, Wis a corporationof Wisconsin Original application Aug. 36, 1962, Ser. No. 220,413, newPatent No. 3,218,706, dated Nov. 23, 1965. Divided and this applicationNov. 17, 1965, Ser. No. 508,208 11 Claims. (Cl. 29568) This patentapplication constitutes a division of our copending US. patentapplication, Serial No. 220,413, filed August 30, 1962, now Patent No.3,218,706 and relates generally to a tool storage and tool changermechanism for a machine tool.

It is a general object of. this invention to provide a unitary toolstorage and tool changer mechanism assembly adapted to be applied as aunit to a machine tool having a tool receiving spindle.

Another object of this invention is to provide a tool storage magazinewith a plurality of tilting tool storage sockets for carrying tools.

A still further object is to provide an improved linkage mechanism fortilting a tool support from a storage position to a tool changeposition.

A still further object of this invention is to provide a tool storagemagazine with a plurality of tilting tool storage supports carried in amanner that an outwardly tilted tool storage support is moved intoabutting engagement with a fixed stop when in a tool change station.

A further object of this invention is to provide a tool storage magazinewith a plurality of indexable tilting tool storage supports that engagea stationary guide track during indexing movement.

A still further object of this invention is to provide a machine toolstructure which is adapted to operably receive an assembly incorporatingtool storage means and a tool changer mechanism.

According to this invention, there is provided an improved andsimplified machine tool having a column and cooperative movable elementscomprising a knee, saddle and workpiece supporting table that arearranged for movement along three mutually prependicular axes forpresenting a workpiece carried by the table to the tool carried by therotatable spindle. The column is provided with a machined fiathorizontal top surface which is adapted to receive a housing that cansupport either an indexable tool storage magazine having a plurality ofstored tools and a tool changer mechanism that is carried in bodilyspaced relationship relative to the storage magazine and the spindle;or, a single tool storage socket and such spaced tool changer mechanism.With either of the tool storage arrangements, the tool changer mechanismis operative to effect an interchange of tools between the storagemagazine and the spindle.

The tool storage magazine of the tool storage and changer unit ismounted in an inclined plane on the upper portion of a housing memberthat is removably secured to a machined surface provided on the top ofthe machine column. The storage magazine is provided with a plurality oftilting tool storage support sockets or receptacles mounted forselective outward tilting movement in closely spaced radial guide slotsformed in the periphery of the magazine drum. With this arrangement, agreater tool carrying capacity is realized due to the fact that thespacing between supports need not provide for the arcuate swing of thetool change arm in gripping a selected tool. The selected tool to begripped is swung out of the circular array and into the arcuate path ofthe tool change arm. Thus, the closer spacing of adjacent tool storagesupports in the circular array of storage positions does not intertedStates Patent fere with the operation of the tool storage mechanism. Thetool storage magazine is rotatably mounted in an inclined plane on asupporting housing which, in turn, is removably secured to thehorizontal top surface of the machine column. The respective tiltingtool storage supports of the inclined magazine are normally retained inan index position in which the longitudinal axis of each tool storagesupport is parallel to the axis of rotation of the magazine. The toolstorage supports with tools carried therein are maintained in retractedindex position by means of a guide track mounted concentrically with theaxis of rotation of the magazine.

To remove a tool from any of the tilting tool storage supports, themagazine is indexed until the selected tool is adjacent the tool changestation. A power actuator is thereupon energized to move a movablesection of the guide track to effect a tilting of the particular supportinto the tool change station. In the tool change station, thelongitudinal axis of the tool carried by the actuated support isdisposed so as to be parallel with the longitudinal axis of the toolspindle.

The storage magazine and tool change unit may be modified to provide asingle tool storage support or socket in the housing. The single storedtool socket is disposed with its longitudinal axis parallel to the axisof the tool spindle. The arrangement is such that the single stored toolis disposed in a position identical to the tool change station intowhich the tiltable support of a selected tool is tilted, as described inconnection with the indexable magazine having the tilting tool storagesupport shown in FIGURE 1. The housing in which the single tool storagesupport is incorporated is similar to the housing on which the indexablemagazine is mounted. As such, the housing is adapted to be assembled tothe machine by simple being bolted on the machined horizontal topsurface of the column. With this arrangeemnt, a single basic machinetool structure may be provided and will accommodate either the housinghaving the indexable magazine with a plurality of tilting tool storagesupports, or the housing having the single tool storage support.

The foregoing and other objects of this invention, which will becomemore fully apparent from the following detailed description, may beachieved by the exemplifying apparatus depicted and set forth in thespecification in connection with the accompanying drawings, in which:

FIGURE 1 is a view in front elevation of a machine tool in which theinvention herein disclosed is incorporated;

FIG. 2 is an enlarged fragmentary view in front elevation of the toolstorage and tool change unit illustrated in FIGURE 1, with a portionbroken away to show the arrangement of the tilting mechanism in relationto the tool storage mechanism at the tool change station;

FIG. 3 is an enlarged transverse view of the tool storage and changerunit taken partly in vertical section and partly in elevation showingthe internal operating mechanism;

FIG. 4 is a perspective view showing in detail the linkage mechanism fortilting the tool storage supports;

FIG. 5 is a fragmentary schematic plan view of the storage magazine ofFIGURE 1 showing the relationship of the stationary guide track, themovable guide track section and the tiltable tool storage supports;

FIG. 6 is a schematic view of the hydraulic control circuit utlized withthe machine; and.

FIG. 7 is a view in front elevation of a machine tool having a modifiedunitary single tool storage and changer unit mounted thereon.

Reference is now made to the drawings and more specifically to FIGURE 1thereof illustrating a machine '8 tool incorporating the variousfeatures of the present invention. As there shown, the machine generallycomprises a base having an upstanding vertical column 21 presenting amachined upper flat surface 22 which is adapted to receive a toolstorage magazine support housing 23. The column 21 is provided withvertical way surfaces 24 on which a vertically movable knee 26 isguidably supported for vertical movement therealong. Transverseguideways 27 provided on the upper surface of the knee 26 slidablysupport the transversely movable saddle 28 upon which is slidablycarried a longitudinally movable work supporting table 30. Poweroperable means [not shown] disposed within the lower portion of thehollow column 2 1 are connected in well-known manner to effect selectiverelative movement of the knee 26, saddle 28 and table 30 along threemutually perpendicular axes. Thus, a workpiece W that is secured to thetable surface 30 may be selectively moved relative to a cutting tool 37operatively secured within a rotatably driven tool receiving spindle 40.The magazine support housing 23 is provided with a complementary fiatmachined surface 41 which is disposed in abutting relationship to thesurface 22 provided on the top of the column 21 with the housing beingsecured in place by means of threaded bolts 42. Access to the interiorof the hollow housing 23 for manipulating the bolts 42 for eithersecuring the housing to the column or removing the housing from thecolumn is had through access openings on either side of the housingwhich are closed by cover plates 43 and 44 that are secured in positionby means of screws [not shown] in well-known manner. The housing 23rotatably supports a tool storage magazine or drum 45 on the upperportion thereof in an inclined plane, as shown in FIGS. 1, 2 and 3. Thestorage magazine 45 is provided with a beveled periphery 46 in which aplurality of equidistanced spaced apart recesses or guideways 47 areformed. Each radially extending recess or guideway 47 is ofpredetermined width and is provided with a pivotable rectangular toolstorage support or receptacle 48 which is adapted to carry a cuttingtool.

In addition to the magazine 45, the housing 23 also carries for relativebodily movement a tool change mechanism or tool transfer devicegenerally identified by the reference numeral 50. The tool changemechanism 50 comprises essentially a carrier or tool change arm 51presenting semi-circular tool gripping recesses 52 and 53 at itsopposite ends. The arm 51 is secured to the outer end of a shaft 54 in abodily spaced relationship relative to the storage magazine 45 and thetool receiving spindle 41) that is rotatably mounted in the column 21. Acover plate 56 and threaded screws 57 serve to retain the arm 51 to theend of the axial movable and rotatable shaft 54. The tool receivingspindle 40, which is the operating member of the machine tool shown, isrotatably driven by power means [not shown] and releasably carries atool, such as the tool 37 shown in FIGURE 1. To selectively limitcertain rotary movements of the tool change arm 51, a pair of fixedstops 57 and 58 are secured to the housing 23 and an axially movablestop 59 is operably carried by the housing. With coordinated movementsof the magazine 45, the tool change arm 51 and movable stop 59, and withthe aid of fixed stops 57 and 58, tools are automatically interchangedbetween the storage magazine 45 and the tool operator or spindle 40.

The construction and arrangement, as well as the operation of the toolchange mechanism 50 and the rotatable spindle 45, as well as the movablestop 59, is set forth in detail in the parent application Serial No.220,413, copending herewith, and reference may be had to thatapplication for the construction and arrangement of these elements if sodesired. Essentially, the tool change arm 51, as previously mentioned,is secured to the outer end of the shaft 54, the latter being supportedin the lower portion of the housing 23 with its axis being disposed inthe vertical plane in which the spindle axis is located.

Rotational movement of the arm 51 in a tool changing operation iseffected through the operation of the shaft 54 which has its rightwardor rearward end, FIG. 3, in splined engagement in a rotatable drivesleeve 61. The drive sleeve 61 is rotatably carried in an internal hub[not shown] provided within the interior of the housing 23 and is drivenby a hydraulic motor 67 schematically shown in FIG. 6.

Axial movement of the tool change arm 51 for withdrawing or inserting atool into a tool storage holder 48 and spindle 40 is effected by meansof a hydraulic power actuator 71 comprising a cylinder 72 which isoperatively secured within the interior of the housing 23 and acooperating axially movable piston rod 74, the free end of which issecured to a block 76. The block 76 has an axial bore through which theshaft 54 extends, being supported therein by means of bearings 79 and 81that are carried within the bore. The inner race [not shown] of thebearing 79 abuts against a shoulder [not shown] formed by the reducedportion of the shaft 54 which passes through the bore of the block 76and serves to effect axially outward movement of the shaft 54 uponleftward movement of the block 76. To provide a connection forretracting the shaft 54 for moving it rightwardly, as viewed in FIG. 3,a snap ring 82 is operatively engaged on the rod 54-to maintain thebearing 81 in operating position within the bore.

To move the carrier or tool change arm 51 and the associated shaft 54axially outwardly, as viewed in FIG. 3, hydraulic pressure fluid issuppiled to the power actuator 71 via hydraulic lines 83 and 84, FIG. 6,which operate to effect leftward movement of the piston rod 74, asviewed in FIG. 3, which is secured to the block 76 and which isoperatively connected to effect axial movement of the shaft 54.

Simultaneously, with the leftward or outward movement of the tool changearm 51 and shaft 54, the movable stop 59 is also moved axial'lyoutwardly with the shaft 54 and tool change arm 51. The movable stop 59comprises a shaft 86 which is slidably carried in a suitable bore formedin the front wall of the housing 23 and presents an integrally formedradial flange 37 that is formed on the outer end of the shaft 86. At itsrightward or inner end, the shaft 86 has a reduced portion 88 that isslidably carried by a cylinder 89 which, in turn, is carried in a boredopening in the block 76. To move the shaft 86 outwardly or leftwandly,as viewed in FIG. 3, the cylinder 89 is connected via a flexiblehydraulic line 91 to the hydraulic line 83 to receive hydraulic pressurefluid simultaneously with the power actuator 72. Thus, as the poweractuator 72 operates to move the shaft 54 and thereby the tool changearm 51 outwardly, it also will effect the outward axial movement of theshaft 86 and thereby the stop 59. However, as the shaft 86 moves withthe shaft 54, hyd'raulic pressure is also supplied to the cylinder 89which thereby imparts an axial independent movement to the shaft 86 sothat it will move axially relative to the shaft 54.

The extent of independent axial movement of the shaft 86 is limited by apositive stop 92 comprising a shoulder screw 93 that is arranged toextend through the end of the cylinder 89 and which is threadedlyengaged in the end of the piston portion 88 of the shaft 36. Hydraulicpressure supplied to the cylinder 89 will force the shaft 86 to moveaxially leftwardly, as viewed in FIG. 3, but its movement is limited tothe spacing that exists between the head of the shoulder screw 93 andthe outer end of the cylinder 89. To retain the shaft 86 in a retractedposition with the shoulder 94 in abutting engagement with the cylinder89 whenever the cylinder is connected to drain, a spring 96 isoperatively positioned around the shaft of the shoulder screw 93 and isdisposed at one end in abutting engagement with the cylinder 89 whileits opposite end abuts the head of the shoulder screw 93. Thus, wheneverhydraulic pressure fluid is connected to actuate the power actuator 72,pressure fluid also flows via the line 91 to the cylinder 89 moving thepiston 88 and shaft 36 outwardly until the flange head 87 of the shaft86 abuts the inner face of the tool change arm 51. After the tool changearm 51 is rotated out of engagement with the movable stop 59, thecontinued supply of hydraulic pressure fluid to the cylinder 89 willurge the shaft 86 further leftwardly until the head of the shoulderscrew 93 abuts the end of the cylinder 89. With the movable stop 59fully extended, the tool change arm 51 will abuttingly engage the stopupon completion of 180 of rotary movenrent of the carrier arm 51 in theextended position.

It is therefore apparent that the positive stop operates to effect theaccurate positioning location of the tool change arm so that toolscarried in the grips 52 and 53 will be axially aligned with the toolstorage support and the spindle 40 so that the tools carried by the armmay be easily inserted into these members.

The tool spindle 41 is rot-atably carried by the column 21 in bodilyspaced relationship relative to the tool change arm 51, as previouslymentioned, in a manner that the axis of the spindle 40 and thelongitudinal axis of either the recess 52 or 53 coincide whenever thecarrier is pivoted from its horizontal parked position to a verticaltool engaging position. The spindle 40 comprises essentially anelongated tubular shaft 191 which is rotatably supported in the column21 in well-known manner. The spindle 40 is driven by a variable speedtransmission mechanism [not shown] which is selectively connectible in awell-known manner to either of spur gear 102 or 103 which are splined tothe spindle shaft 101 and secured thereon by a nut 104.

To facilitate an interchange of tools, the spindle 4%] is provided withan automatic collet 106 constituting a selectively releasable toolclamping means. The co'llet 106 comprises an inner cylindrical hubguided for limited axial movement within an enlarged bore 107 formed inthe spindle shaft 1111. The hub of the coll'et 106 is integrally formedwith a plurality of the forwardly extending resiliently expansiblegripping segments 1% which are disposed in operative position within atapered opening 109 formed in the spindle shaft 101. Axial inwardmovement of the collet 106 operates to engage the resilient segment 1%within the tapered opening 109 of the spindle there-by moving theresilient portions 103 into tight engagement with the shank of a tool.On the other hand, the outward movement of the collet 1116 will serve tomove the resilient segment portions 108 thereof axially leftwardrelative to the tapered bore 169, as viewed in FIG. 3, thereby releasingthe tool so that the tool may be freely withdrawn from the collet. Axialmovement of the collet 1116 in either direction in a tool clamping orreleasing action is accomplished by means of an axially movable rod 110which is secured in the hub portion of the collet 1%, as schematicallyshown in FIG. 6.

To position a tool for an interchange with a tool carried by the spindle4d, the tool storage drum 45 is rotatably carried by a shaft 115, whichis driven by a hydraulic motor 115, shown in FIG. 3, that is mounted ona frame portion 117 of the housing 23. The shaft 115 is rotatablymounted in bearings 118 and 119 and extends through a bored opening 120of an axial boss 121 integrally formed with the drum bolt 45. Bolts 122extend through the boss 121 and threadedly engage in an annular flange123 formed on the shaft 115 to secure the drum in operating position onthe shaft. As previously mentioned, the periphery on the drum 45 isprovided with a plurality of radial slots or guideway-s 47 integrallyformed therein in radial spaced relationship. Each slot or 'guideway 47is of a predetermined width and is provided with a pivotal rectangulartool storage support or receptacle 48 for carrying a tool. In additionto carrying a tool storage support, the spaced parallel sides of eachradial slot or guideway 47 serves to guide the tool storage support 48for pivotal movement. Inasmuch as each rectangular tool storage supportand each cooperating guideway is identical with all the other pivotaltool storage supports and guideways presented by the drum, it is deemedsuflicient to describe in detail only a single tool storage support orreceptacle and g-uideway.

Each tool storage support or receptacle 48 comprises a rectangular blockpivotally supported in its respective slot 47 by means of a pin 131having its opposite end mounted in the drum 45 and projecting through abored opening presented by a shoulder 132 integrally formed with thetool storage support 48, as shown in FIGS. 2 and 4. To carry a tool, thereceptacle 43 is provided wit-h a bored opening 133 which has itslongitudinal axis normally parallel to the axis of drum rotation, andperpendicular to the axis of rotation of the tool storage support orreceptacle 48 about the pin 131. A detent mechanism 134 is provided witheach tool storage support and includes a spring biased ball that isadapted to extend radially into the bore 133 to engage a cooperatingannular groove 135 presented by the tool, as shown in FIG. 3, to therebyreleasably retain a tool in the tool storage support 48.

Inasmuch as each tool storage support 48 is pivotable outwardly aboutits cooperating pivot pin 131, it is necessary to maintain all of thesupporting blocks in upright index position and parallel to the axis ofdrum rotation during indexable tool selection movement of the drum. Tothis end, the radially slotted tool carrying storage drum 45 is providedwith a hollow central portion within which is supported a concentricallydisposed circular stationary main tool guide track or fixed ring whichpresents a peripheral roller guideway 141. At the tool change station35, the main guide track 141) is interrupted to present a peripheralopening for receiving a radially movable track section 142 which isprovided with a roller surface 143 thereon. When the tool storagesupports or receptacles 48 are all in retracted index position, themovable track section 142 will be retracted and will present its rollersurface 143 in annular alignment with the roller surface 141 of the maintrackway so that, in effect, there is one continuous roller surface forthe tool supporting sockets to roll upon, as schematically shown in FIG.5. However, when a tool which has been selected is located in the toolchange station, the pivotal or movable track section 142 will be causedto be moved radially outwardly thereby effecting the pivotable movementof the tool storage support or receptacle 48 about the pin 131 so thatthe tool is projected in the arcuate path of the tool change arm 51.Both the stationary main tool guide track 141? and the movable tracksection 142 are disposed coaxially about a hub 139 in which the drumshaft 115 is supported and is secured to the central frame 117 by bolts144, one of which is shown in FIG. 3. During indexable tool selectingmovement of the magazine 45, the movable track section 142 is in aretracted position, as shown in FIG. 3, in a manner that the arcuateouter roller surface 143 presented thereby coacts with the outer rollersurface 141 presented by the main track section 1411 to provide acontinuous perrpheral roller surface, as shown in FIG. 5. The contrnuous peripheral roller surface, as formed by the roller surfaces 141and 143 of the main track section 140 and movable track section 142respectively, extends through a full 360, and is parallel to the axis ofrotation of the storage drum 45. To provide an operative connectionbetween the tool storage support or receptacle 48, and the continuousperipheral surface presented by the coacting roller surfaces 141 and143, the tool storage support 48 is provided with a pair of guiderollers 14?; and 149 that are rotatably secured to the shoulder 132, asshown in FIGS. 3 and 4. The guide rollers 148 and 149 are supported bythe shoulder 132 for rotation about an axis which is disposedtransversely of the pivot pin 131 about which the tool storage support48 pivots with the rollers 148 and 149 being disposed on opposite sidesof the pin. With the tool storage support 48 in retracted position, therollers 148 and 149 associated therewith are journaled to rotate aboutan axis that is disposed parallel to the axis of drum rotation andperpendicular to the axis of the pivot pin 131 about which theassociated tool storage support 48 is journaled. Therefore, duringindexable movement of the drum 45, the tool storage support 48 is guidedalong the continuous peripheral guide surface by the rollers 148 and149, as shown in FIG. 3, maintaining the longitudinal axis of the toolstorage support 48 parallel with the axis of drum rotation. The toolsare normally carried in a retracted position, i.e., with thelongitudinal axes of the tool storage supports 48 parallel with the axisof drum rotation which, for the sake of clarity in this description, isidentified as the index position for the tools. Thus, even though thedrum 45 is stationary, all tools are held in their index position, andthis is true of the particular tool storage support tha may be locatedin the tool change station 35. This is true, because the rollers 148 and149 associated with each tool storage support 48 are spaced apartsufficiently far enough from each other and are maintained in rollingengagement with the trackway surface. Therefore, any tendency of a tool,such as the tool 37 carried by the support 48, shown in FIG. 3, toeffect a pivotal movement of the associated support in acounterclockwise direction as viewed in FIG. 3, is resisted by theroller 149 which is firmly engaged with the surface 143 of the pivotaltrack section 142. It is therefore apparent that the particular toolstorage support 48 located at the tool change station cannot be pivotedoutward into a tool change position until such time as the pivotal tracksection 142 is moved radially outwardly and downwardly.

In addition to guiding the tool storage supports 48 during indexingmovement of the drum, the radially movable track section 142 is alsooperable to pivot a tool storage support 48 that is located in the toolchange station 35 from the index position to an outwardly disposed toolchange position, as shown in FIGS. 1 and 2, and in broken lines in FIG.3. To accomplish this, the track section 142 is carried for radialoutward movement in substantially spaced parallelism with respect to theaxis of the tool storage support 48. When in the tool change position atthe tool change station 35, the longitudinal axis of the tool storagesupport 48 is parallel with the longitudinal axis of the spindle 40 andpositioned in vertical alignment with the spindle 4t and the axis ofrotation of the arm 51. Thus, a tool storage support 48 is indexablyadvanced by rotation of the storage drum 4-5 to an indexed position atthe tool change station 35 in substantial radial alignment with theradially movable track section 142. To move the tool storage support 48from the index position to the tool change position in the tool changestation 35 for subsequent removal of a tool from the tool storagesupport, the tool storage support 48 is pivoted radially outward aboutits pivot pin 131. As viewed in FIGS. 2 and 3, the movable track section142 is located adjacent to the tool change station 35 in order to pivotthe tool storage support 48 outwardly to the tool change position.Further, as hown in FIG. 2, the movable track section 142 is displacedto the left of a vertical plane which passes through the spindle 40,shaft 54 and tool storage support 48. The movable track section 142 isoffset to the left of such vertical plane in order to provide timedcoaction of the tilting tool storage support 48 with the clockwiseindexing movement of the drum and the counterclockwise rotationalpositioning movement of the drum for positioning a tool into tool changeposition at the tool change station. To pivot the tool storage support48 for locating the too] carried therein in a tool change position whilestill retaining the rollers 148 and 149 in contact with the guidesurface 143 of the movable track section 142, the movable track sectionis moved rectilinearly as well a arcuately about the pivot pin 131 in aradially outward direction.

With the movable track section 142 in a retracted position, as shown infull lines in FIG. 3, it will be apparent that the outer roller surface143 thereof is perpendicular to an imaginary radial line constructed tointersect the rotational axis provided by the pivot pin 131 about whichthe tool storage support 48 is pivotable. With the tool storage support48 pivoted outwardly about the axis of the pin 131, to the horizontaltool change position dcpicited in FIGS. 2 and 4, and also indicated bybroken lines in FIG. 3, the above-mentioned imaginary radial line,constructed perpendicular to the guide surface 143 of the track section,will be .in identical perpendicular relationship to the outer face orroller surface 143 of the pivotal track section 142. Thus, it isapparent that irrespective of the direction of pivotal movement of thetool storage support 48 about its pin 131, the guide rollers 148 and 149rotatably carried thereby are maintained in continuous guidingengagement with the roller surface 143 of the movable track section 142.In this manner, a tool canried by the tool storage support 48 will beaccurately located in a tool change position so that the grip 52 of thetool change arm 51 may easily engage the periphery of the presented toolupon rotation of the arm 51 in a clockwise direction. With the positiveengagement maintained between the guide rollers 148 and i149 and theguide surfaces 143 of the movable track section 142, a minimum oflooseness or :play will exist in each of the tool storage supports orreceptacles 48 as they are moved in an indexing movement.

To achieve this result, the pivotal or movable track section 142 isurged outwardly or to the left from the position it occupies in FIG. 3to assume a horizontal tool clamp position as depicted in FIG. 4 andindicated by broken lines in FIG. 3. In accomplishing this positioningmovement of the movable track section, the track section 142 movesbodily in an arcuate path around the axis of the .pin 131. As a resultof this bodily arcuate movement of the movable track section 142, theouter arcuate roller surface 143 thereof continuously engages therollers 148 and 149 of the tool storage sup-port 48 causing the toolstorage support to pivot about the axis of the pin 131. This movement ofthe movable track section 142 and the resultant pivotal movement of thetool storage support 48 continues until the under surface of the toolstorage support 48 engages an adjustable positive stop comprising a setscrew 151 threaded into a lower integrally formed stirrup bar 152 shownin FIG. 3. When the tool storage support 48 engages the set screw 151,the tool carried by the support will be located in a tool changeposition wherein its axis is disposed in a horizontal plane and the toolprojects into the arcuate path of travel of the tool change arm 51 sothat the grips of the arms may firmly engage with the tool.

To effect the required bodily movement of the movable track section 142there is provided a novel extensible linkage meohanism 155, shown inFIG. 4, and comprising a plurality of spaced, pivotally intersectinglinks that are disposed in symmetrically spaced identical pairs, such asthe pair of links 156 and 156A, At their forward ends, the links 156 and156A are pivotably secured by a pivot shaft 158 to the opposite outervertical faces of inwardly projecting flanges 159 and 161 integrallyformed with the movable track section 142. The shaft 158 constitutes thepivot axis about which the movable track section 142 pivots, while theshaft itself moves bodily about the axis of the shaft 131. It isapparent, therefore, that since the track section 142 pivots about theshaft 158, it will also move bodily about the axis of the shaft 131. Inthis manner, the movement of the track section 142 will cause the toolstorage support 48 to pivot about its axis 131 to move the tool storagesupport 48 from the retracted index position, shown in full lines inFIG. 3, to the horizontal tool change position, depicted in FIG. 4 andindicated by broken lines in FIG. 3. In doing so, the control contactbetween the guide rollers 148 and 149 associated with the storagesupport 48 do not lose contact with the essences guide surface 143 ofthe movable track section so that the pivotal movement of the support isalways under complete control and is never permitted to fall into thetool change position. It is also apparent that the bodily movement ofthe track section 142 about the shaft 131 operates to retain the contactrelationship between the rollers 148 and 1451 and the guide surface 143,and this relationship is maintained throughout the pivotal movement ofthe support 18 so that no sliding between the rollers and the guidesurface occurs. As a :iesult, no wear occurs on the roller sunfaces, noron the arouate guide surface 14-3 of the track section 142, so that nofiat spots are developed on these surfaces.

Since all the linkages in the link mechanism 155 are arranged in pairsand each pair of linkages operates in synchronism, only one ilink ofeach pair of linkages will hereinafter be described to facilitate thedescription.

Rearwardly of the shaft 158, the link 156 is pivotally secured by bolts1'62 and 16 3 to parallel spaced apart movable support links 164 and166. The support links 164 and 16-6, in turn, are pivotaliy secured bymeans of bolts 167 and 1138 to a vertically upstanding flange 169 thatis integrally formed with a linkage support bracket .1711. The supportbracket 17%) is secured by screws 171 to a depending base section .172that is integrally formed with the support base 145 on which the maintrack section 140 is integrally formed. For maintaining the entirelinkage mechanism 155 in synoh-ronism, the rearward link 166 and a matedcompanion link 166A are integrally formed with a transverse bar 173 sothat the structure comprises, in effect, a single unit-airy U-shapedmember. In a like manner, the link 164 and a mated companion link 16 1Aare formed with an inte rally transverse bar 174 to comprise a singleunitary U-shaped member.

At their upper end, the links 164 and led-A are provided with integrallyformed lateral forward extending arms that are pivotally connected bymeans of bolts 176 and 176A to the rearward extending ends of tiltcontrol links .177 and 177A, as shown in FIG. 4. The forward extendingends of each of the control links 177 and 177A are pivotally connectedto the extending ends of a shaft 1'73 that extends through suitablebored holes in the inwardly extending track section flanges 159 and 161.Between the flanges 159 and 16 1, the shaft 178 carries a freely movablecollar or sleeve 179 that is secured to the outer end of a piston rod181 which is axially movable by the operation of the piston [not shown]that is reciprocable within a cylinder 182 which constitutes a poweractuator 183 for effecting the pivotal tilting movement of the toolstorage support 48. The opposite end of the cylinder 182 is pivotallysecured by a bolt 184 to spaced apart vertical flanges 1515 that areintegrally formed with a linkage support bracket 170.

For operating the power actuator 183 to move a tool storage support 48firom a retracted index position to the tool change position, hydraulicpressure fluid is supplied to the power actuator cylinder 182 via aconnecting line 186, while a line 187, having one end connected to theopposite end of the cylinder as depicted in 'FIG. 3, is connected todrain. Conversely, to return the tool storage support 4% from the toolchange position, that it occupies in PEG. 4, to the retracted indexposition shown in full lines in FIG. 3, pressure fluid is supplied tothe cylinder via the line 1&7 while the line 186 is simultaneouslyconnected to drain.

In addition to supporting a tool in the index position, as well as inthe tool change position, the tool storage support 48 functions as amovable stop limiting counterclockwise movement of the drum 45 to elfectthe final positioning of the tool storage support in the tool changestation. To this end, when the drum 45 is rotated in a clockwisedirection, as viewed in FIGURE 1 in a tool sel cting movement, theselection of a tool will cause the drum 1-5 to stop rotating but itsposition will be such that the tool storage support in which the desiredtool is stored will be slightly to the left of a vertical plane whichpasses through the tool change station 35, the axis about which the toolchange arm rotates, and the axis of rotation of the spindle 40. The drum45 will then be operated in a reversed or counterclockwise directionand, at the same time, the tool storage support 48 in which the selectedtool is stored will be pivoted outwardly from the index position to ahorizontal position, as depicted in FIGURE 1. With the tool storagesupport 48 in a tilted outward tool change position and with the tooldrum 45 rotating in a clockwise direction, the outwardly tilted toolsupport will be disposed so as to engage with a positive stop 190 thatis fixedly secured to the houSing 23. It is apparent, therefore, thatcounterclockwise rotation of the drum 45 for effecting final positioningof the outwardly tilted tool storage support 48 will move one side ofthe tool storage support into abutting engagement with the fixedpositive stop 1%, as shown in FIGS. 1 and 2, terminating thecounterclockwise rotation of the drum 45. It is emphasized, however,that the tool storage support 48 is only in a line of interference withthe fixed positive stop 190 when it is in the tilted outward tool changeposition. Therefore, when the tool storage support 48 is in theretracted or index position it will pass the fixed stop 190 irrespectiveof direction of drum rotation. It will be understood, that during theprimary indexing movement of the storage drum 4-5, the next selectedtool is moved beyond the positive stop 1% in a clockwise direction; thetool storage support 48 is then tilted outwardly; and, the drum rotationreversed to urge the outwardly tilted tool storage support into abuttingengagement with the positive stop 19% so that the selected tool carriedby the outwardly tilted tool storage support 48 will be accuratelylocated in the tool change station and in position to be engaged by atool grip on the tool change arm 51.

The operation of the tool change magazine 45 is set forth in detail inthe aforementioned co-pending parent US. application, Serial No.220,413. Generally, the drum 45 is rotatably driven in a clockwisedirection, as viewed in FIGURE 1, for indexing the drum to begin amachining cycle, as well as for advancing subsequent tools to the toolchange station after a machining cycle is begun. At the beginning of amachining cycle, the initial clockwise rotation of the drum 45 operatesto position a first code identified tool to be used in the machiningcycle adjacent the tool change station 35. To this end, the codeidentified tool is provided with a slightly longer shank and extendsdownwardly through the bore of the tool storage support 48 a sufficientdistance to actuate a limit switch to indicate the beginning of themachining cycle and condition the control circuit for subsequentlymoving that tool into the tool change station. As the first tool orcoded tool actuates the limit switch 195, the drum will continue to bedriven in a clockwise direction a distance sufiiciently far enough untila guide roller 14-? associated with a different augularly spaced aparttool storage support 48 actuates a sequence control limit switch 196which is carried by a mounting block 197 that is secured to an inclinedweb portion 1%, as shown in PEG. 3. The reversing control limit switch196 is disposed substantially 180 from the tool change station in aposition to be actuated by a roller 149 of a support at the time thatthe particular storage support with the selected tool or first tool hasbeen rotated in a clockwise direction past the tool change station.Therefore, with the particular tool storage support 418 a slightdistance to the left of the tool change station 35, as viewed in FIGURE1, the limit switch 1% will be actuated to cause the magazine 45 to berotated in a reverse or counterclockwise direction, as viewed in FIG-URE l. The limit switch 1%, upon being actuated, also operates to effectthe operation of the power actuator 183 which effects the pivotalmovement of the tool storage support 48 carrying the first tool in themachining cycle into the tool change station as the drum begins torotate in a counterclockwise direction. In other words, counterclockwiseor reverse movement of the drum 45 and the energization of the actuator183 occurs simultaneously so that the drum is moved in a reversedirection and, at the same time, the movable track section 142 will bemoved outwardly and downwardly about the axis of the shaft 131 so thatthe tool storage support 48 carrying the first tool 37A is also pivotingabout the axis of the shaft 131. This movement of the tool storagesupport from the index position into a tool change position will becompleted prior to the time that the tool storage support is actuallylocated in the tool change station so that the continuedcounterclockwise or reverse movement of the drum will cause the side ofthe tool storage support that is now tilted forwardly or outwardly toengage the positive stop 190 and thus eflect final precise positioningof the tool storage support in a tool change position at the tool changestation 35.

The hydraulic circuit for supplying operating pressure to control theoperation of the machine tool is schematically shown in FIG. 6. As thereshown, an electric motor 201 is connected to drive a hydraulic pump 202to withdraw fluid from a sump 203 through a line 204 and discharge thefiuid under pressure into a main supply line 206. A pressure reliefvalve 207 is connected in parallel with the pump 202 to the lines 204and 206 to maintain a predetermined pressure in the hydraulic circuit.

The function of the hydraulic circuit is best illustrated in conjunctionwith a tool interchange cycle of operation. It will be assumed that thefirst code tool 37 of the group of tools 37, 37A and 37B that are to beused in a particular machining cycle is to be moved into the tool changestation 35. It will also be assumed that the spindle 4% with the lasttool 36A of a previous group of tools, namely, 36 and 36A, is performinga final work operation on a workpiece for completing a cycle ofmachining opera tions which are entirely different than the operationswhich will be performed on a diflerent workpiece with the group of tools37, 37A and 37B.

When the last machining operation has been completed with the tool 36A,2. signal calling for a change of tools, initiated either manually orfrom a programmed source, is obtained to thereupon effect thedeactuation of a spindle drive clutch [not shown] in a well-known mannerto interrupt the power drive to the spindle 40 and to actuate thespindle brake 210, shown schematically in FIG. 6, to stop spindlerotation. The spindle brake 210 operates under the control of a solenoidactuated valve 211 which is actuated by a solenoid 212 energized by thesignal that calls for a change of tools. Energization of the solenoid212 actuates the valve 211 so that it operates to direct pressure fluidin the main supply line 206 and a connecting branch line 213 into aconnected line 214 that is in communication with the hydraulic actuator210A that is associated with the spindle brake 210. Pressure fluidsupplied to the actuator 210A will effect the operation of the brakemechanism 210 to stop the rotation of the spindle 40.

After the spindle 40 has been braked to a stop, a solenoid 216associated with a control valve 217 is deenergized, and simultaneouslytherewith, an associated solenoid 218 is energized. This will eflect theoperation of the motor 116 in a direction to move the magazine in aclockwise direction for moving the first tool 37 into the tool changestation 35, and simultaneously therewith, for effecting the retractingmovement of the tool storage support 48 in which the tool 36 is storedand which is presently located at the tool change station. To this end,the energized solenoid 218 actuates the valve 220 and it operates todirect pressure fluid from the main supply line 206 and a connectedbranch line 219 into a line 221 that is connected to an inlet port ofthe motor 116. Pressure fluid supplied to the motor 116 via line 221will effect the operation of the motor in a direction to urge the drum45 in a clockwise direction. Simultaneously, pressure fluid will flowfrom the line 221 into the connected line 137 and thence into the rodend of the cylinder 182 to effect the tilting movement of the toolstorage support 48 in which the tool 36 is stored into a retracted indexposition. As pressure fluid is supplied to the motor 116 via the line221, exhaust fluid will flow from the motor into a connected line 222through the valve 217 into a connected line 223 that is in communicationwith a main return line 225 leading to the reservoir 203. The rate offlow of exhaust fluid flowing into the return line 225 from allhydraulically operated units, except the spindle brake 210 and the motor67, is controlled by an adjustable flow control valve 226 that isinterconnected in the line 225. Since the hydraulic actuator 183 hasbeen energized to effect the retraction movement of the tool storagesupport 48, exhaust fluid from the right end of the cylinder 132, asviewed in FIG. 6, will flow into the connected line 186 that is incommunication with the line 222. Thus, the exhaust fluid from theactuator 183 combines with the exhaust fluid from the motor 116 and isreturned to the reservoir 203 as previously described.

As the magazine 45 is rotated in a clockwise direction, the first tool37 of the group of tools 37, 37A and 37B, is a code tool and it willactuate a limit switch 195 shown in FIGS. 2 and 3. Only the first orcode tool will actuate the limit switch 195 because it is provided witha shank extension 136 that is removably attached to the inner end of thetool as depicted in FIG. 3. With the extension 136 attached to the firsttool 37, the shank of the tool extends inwardly sufficiently far so thatit will engage the actuating arm of the limit switch 195 to actuate theswitch as the tool moves with the drum 45 in a clokwise direction. Asshown in FIGS. 2 and 3, the limit switch 195 is carried by the guidewaysupporting base and is located to the right of the tool change station35, as depicted in FIG. 2. However, prior to the code tool 37 actuatingthe limit switch 195, a roller 149 associated with a storage support 48,which is located diametrically opposite the support in which the tool 37is stored, will actuate and release the limit switch 196. This prioractuation and deactuation of the switch 196 conditions the controls forsubsequent operation. The drum 45 continu-es to rotate in clockwisedirection and the code tool 37 passes the switch 195, actuating anddeactuating the switch. Drum rotation will continue in a clockwisedirection, moving the tool 37 to the left of the tool change station 35,as viewed from the front of the machine. As the drum 45 continues torotate in a clockwise direction, the roller 149 associated with thesupport that is immediately to the left of the support which is locateddiametrically opposite the support in which the tool 37 is stored, willactuate the limit switch 1196 again, and drum rotation in a clockwisedirection is stopped. To this end, when this condition is obtained,i.e., with the limit switch 196 actuated twice and with the interveningactuation of the limit switch 195, the solenoid 218 ascociated with thecontrol valve 217 is deenergized. This will actuate the control valve217 so that it operates to interrupt the flow of pressure fluid to themotor 116 stopping the clockwise rotation of the drum 45. Simultaneouswith the deenergization of the solenoid 218, the associated solenoid 216is energized to operate the valve to direct pressure fluid to the motor116 to operate it in a reverse direction for rotating the drum 45 in acounterclockwise direction.

At the same time, pressure fluid will flow into the line 186 and thenceinto the right end of the cylinder 182 of the actuator 183. This willcause the actuator 133 to operate to move the movable track section 142outwardly thereby effecting the pivotal movement of the tool storagesupport 4-3 in which the first tool 37 is stored outwardly from an indexposition into a horizontal tool change position. Thus, thecounterclockwise rotation of the magazine 45 and the outward pivotalmovement of the tool storage support 4-3 occurs simultaneously. Thecounterclockwise rotation of the drum 45 continues until the outwardlypivoted support 48, in which the tool 37 is stored, engages the positivestop 190 to terminate the counterclockwise rotation of the drum and toposition the first tool 37 in the tool change station. However, at thistime, pressure fluid will be continued to be supplied to the motor 116so that it operates to continuously urge the magazine 45 in acounterclockwise direction thereby positively holding the magazineagainst the positive stop 1%. With the first tool 37 positioned in atool change position at the tool change station, after a slight timeddelay, a solenoid 227 associated with a control valve 228 is energizedto effect the operation of the valve for directing pressure fluid to theactuator 71 for positively retaining the tool change arm 51 in theretracted position prior to a tool change operation. With the solenoid227 energized, the valve 228 is actuated and operates to direct pressurefluid from the supply line 206 into a connected line 229 thatcommunicates with the rod end of the cylinder 72. Pressure fluidsupplied to the rod end of the cylinder 72 will maintain the rod 74associated with the actuator 71 in a retracted position so that the toolchange arm shaft 54 and the shaft 86 associated with the movable stop 59are retained in retracted position. With pressure fluid being suppliedto the rod end of the cylinder 72, the left end of the cylinder isconnected to drain via the interconnected lines 84 and 83 which, byoperation of valve 228, communicate with the main return line 225.Simultane-ous therewith, the cylinder 89 associated with the movablestop 59 is also connected to drain via a connecting line 91 thatcommunicates with the line 83.

Simultaneously with the energization of the solenoid 227 associated withthe valve 228, a solenoid 231 associated with a control valve 23h: isenergized to erfect the clockwise rotary movement of the tool change arm51 so that the arm will be moved from the horizontal parked position toa vertical tool engaging position. This movement of the arm 51 iseffected by the energization of the solenoid 231 which effects theactuation of the control valve 23!) so that the valve operates to directpressure fluid obtained from the supply line 2% and a connected branchsupply line 232 into a line 233 that is in communication with an inletport of the motor 67. The pressure fluid supplied to the motor 67 viathe line 233 will effect the operation of the motor for rotating thetooi change arm '1 in a clockwise direction, as viewed in FIGURE to movethe arm from its horizontal parked position into a vertical toolengaging position. As the motor 67 operates to effect the rotation ofthe arm in a clockwise direction, exhaust fluid from the motor 437 willflow into a connected line 234 and will be directed by the valve 230into a branch return line 236, with the exhaust fluid flowing through aflow control valve 237 that is adjustable so as to vary the rate ofdischarge therethrough so that a predetermined rate of rotary movementof the arm 51 may be established as desired.

When the tool chan e arm 51 has rotated to a vertical position, whereinit has grasped the tool 37 and the 0] 36A, a limit switch 237, shown inFIG. 3 and schematically in FIG. 6, will be actuated. Actuation of thelimit switch 237 is accomplished by means of a cam 238 or a cam 239carried in diametrically opposite relationship on the peripheral surfaceof a cam disc 24%) which is secured on the shaft drive sleeve 61 forrotation therewith. The limit switch 237 is arranged to be actuated byeither the cam 238 or on alternate cycles of rotation by the c am 239.Thus, in the initial rotation of the arm 51 from a parked position to avertical tool engaging position, the cam 238 will actuate the limitswitch 237. It will be noted that only one cam actuates the limit switch237 during one interchange cycle of operation and the other cam, spaced180 apart therefrom, actuates the switch during an alternate cycle.

Thus, when the arm 51 is in a vertical position, the limit switch 237will be actuated by either the earn 238 or the cam 239 to maintain thesolenoid 216 associated with the valve 217 energized so that theoutwardly tilted tool storage support 48, in which the tool 37 isstored, is maintained against the positive stop 1%. The actuated limitswitch 237 also effects the deenergization of the solenoid 227 so thatthe control valve 228 is actuated into a neutral position for subsequentoperation. The actuated limit switch 237 further operates to effect theenergization of a solenoid 243 associated with a control valve 244 toactuate the valve so that it operates the direct pressure fluid from thesupply line 266 via an interconnecting line 245 into a connected line246 that communicates with the left end of a cylinder 247 of a colletactuator 248. With the cylinder 247 supplied with pressure fluid via theline 246, a rod 243 is moved outwardly of the cylinder to the right, asviewed in FIG. 6, into engagement with the actuating rod 251) that isconnected to the collet M6. The rightward movement of the collet rod 250will actuate the collet 106 so that the resilient segments 108 of thecollet are released from tool clamping engagement. Thus, the too 36A,which is presently in the spindle dit, is released so that it may bewithdrawn from the spindle. As the actuator 248 is operated to effectthe unclamping of the collet, the rod end of the cylinder 247 isconnected to the return line 225 via the interconnected lines 251 and252.

The actuated limit switch 237 also operates to effect the energizationof a solenoild 253 associated with the control valve 228 to effect theactuation of the valve so that it operates to direct pressure fluid fromthe supply line 296 into :the interconnected lines 33 and 84 to supplythe left end of the cylinder 72, as viewed in FIG. 6, with pressurefluid. Pressure fluid supplied to the left end of the cylinder 72 willeffect the operation of the actuator '71 to move the rod 74 associatedwith the cylinder outwardly to the right, as viewed in FIG. 6, or to theleft, as viewed in FIG. 3. This outward movement of the rod 74 effectsthe simultaneous outward or leftward movement, as viewed in FIG. 3, ofthe arm shaft 54 and movable stop shaft d6. Thus, the tool chan e arm 51is moved outwardly away from the front face of the machine toolwithdrawing the tool 37 from the .tool storage support 4-8 located atthe tool change position and to withdraw the tool 36A from the spindledd. At this time, the exhaust fluid from the right rod end of thecylinder 72 passes into the connected line 22.9 which is connected tothe reservoir by operation of the valve As pressure fluid is beingsupplied to the left end of the actuator '71, the pressure fluid in theline 33 wi l also flow into the connected line 1 and be directed therebyinto the cylinder 8? to act on the reduced piston portion of the rod asto bias the rod 8d outwardly or to the left, as viewed in FIG. 3. Aspreviously described, the hydraulic pressure supplied to the cylinder8-9 will condition the shaft 86 for further leftward movement after thearm 51 has been rotated in a clockwise direction from a verticalextended position to release the stop 59. When this occurs, the rod 86will move an additional amount to the left, as viewed in FIG. 3, so thatthe head 87 extends into the path of rotation of the arm 51 forsubsequent engagement by the arm.

When the arm 51 is in fully extended position, a cam secured to theblock 76 is moved into position to engage the actuating arm of the limitswitch 255. Actuation oi the limit switch 755 effects the energizationof the sole noid 231 associated with the control valve 230 to actuatethe valve so that it operates to direct pressure fluid from the branchsupply line 232 through the valve into the con nected line 233 forsupplying the hydraulic motor 67 with pressure fluid to cause it tooperate in a direction to effeet a of rotational movement of the arm 51in a clockwise direction, as veiwed from the front of the machine tool,from the vertical position that it occupies as depicted in FIG. 3. Thecarrier arm 51 wtih the two tools 37 and 36A in the grips 52 and 53,respectively, will rotate l8il in a clockwise direction until the armabus the extended movable stop 59 wherein the flanged head 87 of thestop will intermeshingly engage a slot 256 that is formed in the side ofthe arm 51 adjacent to the grip 53. The engagement of the arm 51 withthe movable stop 59 will stop the rotary movement of the arm 51. Thus,the position of the two tools 37 and 36A have been interchanged so thatthe tool 37 in the grip 52 is now axially aligned with the spindle 40while the last tool 36A, of the previous group of tools that is carriedby the arm grip 53, is axially aligned for insertion into the outwardlypivoted tool storage support 48 that is located in the tool changestation in which the tool 37 was stored. With the arm 51 positioned 180into a tool interchange position, the limit switch 237 is again actuatedby one or the other of the cams 238 or 239 to effect the next step inthe tool change cycle of operation.

To retract the carrier arm 51 for inserting the tool 37 into the spindleand tool 36A into the tool storage support 48, the solenoid 227associated with the control valve 228 is energized while the solenoid253 associated with the valve is simultaneously deenergized. Theenergization and deenergization of the solenoids 227 and 253,respectively, is elfected upon the actuation of the limit switch 237which is accomplished at the end of the 180 rotation of the arm 51.Energization of the solenoid 227 will actuate the valve 228 so that thevalve operates to direct pressure fluid into the line 229 which isconnected to the rod end of the cylinder 72. The actuator 71 isthereupon operated to effect a retraction of the arm 51. As pressurefluid is supplied to the rod end of the cylinder 72, the left end of thecylinder is connected to drain via the lines 84 and 83, andsimultaneously therewith, the cylinder 89 is also connected to drain viathe line 51 that is connected to the line 83. Thus, the combined exhaustfluid from the left end of the cylinder 72 and from the cylinder 89 isdirected by the valve 227 into the return line 225.

As the actuator 71 is operated to effect inward movement of the arm 51,the cam 254 carried by the block 76 is moved out of engagement with theactuating arm of the limit switch 255. This merely conditions the limitswitch for subsequent actuation in the next sequence of operation. Whenthe arm 51 is fully retracted, a earn 256 secured to the block 76 ismoved into engagement with the actuating arm of a limit switch 257 toactuate the limit switch. Actuation of the limit switch 257 effects thedeenergization of the solenoid 243 associated with the collet controlvalve 244 to actuate the valve into its normal operating position. Withthe valve 244 in its normal operating position, pressure fluid from thesupply line 206 and the connected line 245 is directed into theconnected line 251 that is in communication with the rod end of thecylinder 247. This will effect the operation of the actuator 24?, tomove the associated rod 249 inwardly to disengage it from the colletactuating rod 250. The collet actuating rod is thereby released and aspring 258 that is associated with the rod 250 urges the rod in aleftwardly direction, as viewed in FIG. 6, so that the resilientelements 108 of the collet are tightly engaged with the shank of thetool 37 now within the spindle 40 to firmly clamp the tool in operatingposition in the spindle. Exhaust fluid from the left end of the cylinder247 is directed to drain via the line 241, the valve 238 and theconnecting drain line 252.

The actuation of the limit switch 262 also effects counterclockwiserotation of the carrier arm 51 to disengage the carrier arm from thetools and rot-ate it in a counterclockwise direction from a verticalposition to a horizontal parked position. During the counterclockwiserotation of the arm 51, the solenoid 227 associated with the valve 228is retained energized to maintain the carrier arm 51 in a retractedposition while it is being rotated to the parked position.

To rotate the carrier arm 51 90 in a counterclockwise direction from avertical position to a horizontal parked position, the actuated limitswitch 257 is connected .to effect the deenergization of the solenoid231 and simultaneously therewith to effect the energization of asolenoid 265 associated with the control valve 230. With the solenoid265 energized, the valve is actuated and operates to direct pressurefluid from the branch supply line 232 through the valve and into theline 234 that communicates with an inlet port of the hydraulic motor 67.Pressure fluid supplied to the motor 67 via the line 234 will operatethe motor in a direction to effect the rotation of the arm 51 in acounterclockwise direction, as viewed from the front of the machine. Aspressure fluid is supplied to the motor 67 via the line 234, exhaustfluid from the motor will flow into the line 233 and by operation of thevalve 230 will be directed into the return line 236. Thecounterclockwise rotation of the arm 51 will continue until a cam 266carried by a cam disc 267, shown schematically on FIG. 6 as beingsecured to the shaft 54 but which is actually secured to the rotarydrive sleeve 61 shown in FIG. 3, actuates a limit switch 268. The limitswitch 268 upon being actuated will effect the deenergization of thesolenoid 265 associated with the control valve 230. The valve 230 willthereupon be actuated to a neutral position and operates to interruptthe flow of pressure fluid to the hydraulic motor 67, with the arm 51 ina horizontal parked position against the positive stop 57. It will benoted that the cam disc 267 is provided with a second cam 269 which islocated on the peripheral surface of the disc diametrically opposite thecam 266. The cams 266 and 269 are disposed in position so that uponrotation of the disc 267 in one direction or the other, one or the otherof the cams will actuate the limit switch 268 to terminatecounterclockwise rotation of the arm 51. It is to be noted that only onecam actuates the limit switch 268 during one interchange cycle ofoperation and that the other cam, spaced 180 apart therefrom, actuatesthe switch during an alternate cycle.

After the arm 51 has been rotated in a counterclockwise direction to theparked position actuating the limit switch 268, the actuated limitswitch 268 effects the deenergization of the solenoid 212 associatedwith the brake actuator valve 211 and the valve is actuated to block theflow of pressure fluid t0 the hydraulic actuator 219A of the brakemechanism 210 and simultaneously connect the hydraulic actuator 210A todrain. This will release the brake mechanism 210 so that the spindle 40,with the tool 37 secured therein, is free to rotate. With the brakemechanism 210 released, the spindle drive clutch mechanism (not shown)is again engaged to reestablish the drive connected to one or the otherof the spindle drive gears 103 or 104, shown in FIG. 3.

As the spindle 40 is being operated in a work operation with the codedfirst tool 37, the magazine 45 is again indexably rotated in a clockwisedirection to move the tool storage support 48, in which the previouslyused last tool 36A of the previous group of tools is stored, out of thetool change station 35 and to position the next tool storage support 48,in which the second tool 37A of the new group of tools is stored, intothe tool change station 35. However, the tool storage support 48, withthe previously used tool 36A stored therein, is still in an outwardlytilted tool change position and therefore must be tilted or retractedinwardly to an index position. Both the retraction of the tool storagesupport 48 and the clockwise rotation of the drum 45 for positioning thenext tool in a tool change station is accomplished simultaneously.

To effect the simultaneous energization of the drum motor 116 and thestorage support tilt actuator 183 to move the tool storage support froma tool change position to a tool index position simultaneously with theinitiation of clockwise rotation of the drum 45, the solenoid operatedcontrol valve 217 is actuated by enerizing the associated solenoid 218and simultaneously therewith deenergizing the solenoid 216 associatedwith the valve. The simultaneous energization and deenergization of thesolenoids 218 and 216 respectively, is efiected upon the actuation ofthe limit switch 268 which was accomplished when the arm 51 was rotatedto its parked position, as previously described. With the solenoid 218energized, the valve 217 is actuated and operates to connect the supplyline 286 via the connected branch line 219 to the line 221 that isconnected to an inlet port of the hydraulic drum motor 116. The pressurefluid supplied to the motor 116 via the line 221 will effect theoperation of the motor-116 for driving the drum 45 in a clockwisedirection. As the fluid motor 116 operates to drive the drum 45 in aclockwise direction, exhaust fluid from the motor will return to thereservoir 283 via the line 222, the valve 216, the line 223, and thereturn line 225.

The pressure fluid supplied to the line 221 will also flow into theconnected line 187 which is in communication with the rod end of thecylinder 182 of the tilt actautor 183. Pressure fluid is supplied to theactuator 183 via the line 187 and will effect the operation of theactuator so that it will operate to effect the inward retracting tiltmovement of the tool storage support 48 in which the tool 36A is storedinto an index position. As the actuator 1 83 operates to retract thesupport 48, exhaust fluid from the cylinder 182 will ilow via the line186 into the line 222 to combine with the exhaust fluid from the motor116.

With the motor 116 operating to drive the drum 45 in a clockwisedirection for moving the tool storage support 48, in which ths secondtool 3 7A of the new group of tools is stored, into the tool changestation 35, the tool 37A moving with the drum will move past the switch195. Since only the first tool 37 is coded, it is the only tool thatwill actuate the limit switch 195. Therefore, as the second tool 37A,carried by the tool storage support 48, moves past the limit switch .195it will not actuate the switch. However, the roller 149 associated witha directly oppositely located tool storage support will actuate thelimit switch 196. At this time, however, the actuation of the limitswitch 196 has no effect on the control system for the arrangement issuch, that after the initial actuation of the code limit switch 195, thelimit switch 196 must be actuated twice to have any elfect in thecontrol system. Therefore, as the tool storage support 48, carrying thesecond tool 37A, moves through the tool change station 35 to a positionto the left thereof, as viewed from the front of the machine, the roller149 of the following tool storage support 48 adjacent the diametricallyoppositely located tool storage support will actuate the limit switch196- a second time in this sequence. With the limit switch 196 actuatedtwice, the solenoid 218 associated with the drum rotation control valve217 is deenergized so that the valve is actuated to terminate theclockwise rotation of the drum 45. Simultaneously therewith, thesolenoid 216 associated with the valve 217 is energized and actuates thevalve for directing the pressure fluid to the motor 116 to operate it ina direction to effect a counterclockwise rotation of the drum 45 andalso simultaneously therewith, to supply pressure fluid to the tiltactuator 183 for moving the tool storage support 48, in which the tool37A is stored, outwardly into a tool change position. As previouslymentioned, the counterclockwise rotation of the drum 45 continues untilthe outwardly tilted support 48 engages the positive stop 190 to stopthe counterclockwise rotation of the drum 45.

With the second tool 37A of the group of tools 37, 37A and 37B locatedoutwardly in horizontal tool change position of the tool change station35, a complete tool change cycle has been accomplished. The second toolchange cycle of operation will not again be initiated until the toolchange button [not shown] is again actuated to initiate a second cycleof arm movement to interchange the second tool 37A with the first tool37.

An electrical circuit, of which the variously described limit switchesare a part, has not been illustrated as it is not believed that such acircuit is necessary for full understanding of the invention set forthherein. However, an electrical circuit, suitable for the machine shown,is set forth in detail in the aforementioned co-pending US. patentapplication, Serial No. 220,413.

In FIG. 7, there is represented a modification of the invention in whichthe tool change carrier 50X is operatively disposed to effect aninterchange of tools between the tool spindle 40* and a single storagesocket 275.

The basic portions of the machine structure, comprising the column 21,saddle 28, knee 26 and table 30, as well as the spindle 40, are allidentical to the structure illustrated in FIGURE 1, and therefore, theidentical parts will be identified by the same identifying numberspreviously used. The tool spindle 40 is provided with the tool clampingcollet 106, shown in FIG. 3, together with the associated controlapparatus represented schematically in the hydraulic diagram of FIG. 6.As previously mentioned, common reference numbers have been applied toidentify identical parts hereinbefore described, shown on the drawings.The tool change carrier 50X is operatively carried by a modified hollowhousing structure 276 for coordinated rotatable and axial movementrelative to positive stops 57X and 58X. The frame or housing 276 isprovided with a flat machined undersurface 277 for hearing engagementwith the machined surface 41 provided on the top of the column 21previously described. The housing 276 is removably mounted on the topsurface 41 of the column 21 in the same manner as the frame or housing23 being secured there in postion by means of the bolts 42. Cover plates279 and 281 on either side of the housing 276 are removably secured inposition by means of screws [not shown] and provide access into theinterior of the housing 276 for manipulating the bolts 42 for securingor removing the housing 276 to or from the column 21. A movable stop 59Xis likewise movably carried by the frame or housing 276 and operatesboth as a positive stop and as a movable guide member, as previouslydescribed. The tool change arm 51X of the tool changing mechanism 50X isoperatively disposed relative to the tool receiving spindle 48 and thesingle stationary tool receiving storage socket 275 that is provided inthe upper portion of the hollow housing 276. The stationary storagesocket 275 is positioned in parallel spaced relationship to the toolreceiving spindle 40 that is journaled in the upper portion of themachine colunm 21. The single storage socket 275 is adapted to removablysupport a tool in the same tool change station 35 described inconnection with the tiltable support storage drum represented in FIGURE1.

In operating a machine incorporating the modification shown in FIG. 7, atool would manually be withdrawn from the single storage socket 275 andreplaced with the next tool required for the next machining operation.This manual removal of the tool from the storage socket would beaccomplished while a machining operation with the tool in the spindle isin progress. Thus, at the completion of a machining operation by onetool, the next required tool is positioned in the stationary storagesocket 275 in readiness for a tool change cycle.

With the pair of tools respectively mounted in the storage socket 275and the tool spindle 48, the tool change carrier arm 51X is operated toeffect an interchange of tools therebetween. The operation of the toolchange mechanism in a tool change cycle is identical to thathereinbefore described in detail with reference to the other drawings.However, since no preliminary positioning or indexing movement of astorage magazine is necessary, the operating controls are simplified. Inall other respects, the operating controls previously described inconnection with the hydraulic diagram, shown in FIG. 6, applies thesimplified modification of the invention, shown in FIG. 7.

From the foregoing detailed description of the illustrative embodimentssets forth herein to exemplify the present invention, it will beapparent that there has been provided an improved tool change mechanismin combination with the novel tool storage means.

Although the illustrative embodiments of the invention have beendescribed in considerable detail for the purpose of disclosing apractical operative structure whereby the invention may be practicedadvantageously, it is to be understood that the particular apparatusdescribed is intended to be illustrative only and that the various novelcharacteristics of the invention may be incorporated in other structuralforms without departing from the spirit and scope of the invention asdescribed in the subjoined claims.

The principles of this invention having now been fully explained inconnection with the foregoing description, we hereby claim as ourinvention:

1. In a machine tool:

a base;

a column mounted on said base and extending upwardly therefrom;

a removable housing mounted on the top of said column;

means securing said housing to said column in operating position;

a tool receiving spindle journaled in said column;

tool storage means supported by said housing for storing the tools thatare to be used in said spindle;

a tool transfer member movably carried by said housing for interchangingtools between said spindle and said storage means; and,

actuating means mounted in said removable housing and connected to saidtool transfer member for actuating said member in its movements forperforming the tool transfer operation.

2. A machine tool according to claim 1 including:

a machined surface on the top of said column; and

a machine surface on the bottom of said housing for engagment with themachined surface of said column so that when said machined surfaces arein engagement, said housing constitutes an upward extension of saidcolumn.

-3. A machine tool according to claim 1 wherein said tool storage meanscomprises:

a magazine having a tool change station and being adapted to carry aplurality of tools for use in said spindle, said magazine being movablysupported by said housing for individually moving said tools into thetool change station; and,

said tool transfer member comprises an arm rotata'bly supported by saidhousing for engaging and transferring it to said spindle and forengaging the previously used tool in said spindle and transferring it tothe tool change station.

4. In a machine tool:

a frame;

a tool receiving spindle journaled in said frame for operating a tool ina work operation;

a tool storage magazine carrying a plurality of tools for use in saidspindle and being rotatably mounted for individually moving the toolsinto a tool change station;

abutment means engaged by said magazine upon rotation thereof forstopping such rotation to locate the succeeding tool at the tool changestation; and,

tool transfer means actuatable to interchange the tools between saidtool change station and said spindle.

5. A machine tool according to claim 4 wherein said abutment meanscomprises:

a fixed stop mounted on said frame;

an abutment carried by said magazine for movement between a retractedinoperative position and an extended position wherein it is located inthe path of said fixed stop; and,

actuatin means responsive to the approach of the selected tool into thetool change station to shift said abutment to its extended positionwherein it is moved with the rotation of said magazine into engagementwith said stop for stopping the rotation of said magazine when thesucceeding tool is located in the tool change station.

6. A machine tool according to claim 5 wherein said abutment meanscomprises:

a plurality of tool receptacles carried by said magazine for movementindividually into the tool change station by the rotation of saidmagazine, said receptacles being mounted for pivotal movement between aretracted position and an extended position relative to said magazine;and,

an abutment face on each of said receptacles in position to be disposedin the path of said fixed stop when the associated stop is located inits extended position so that said abutment face will engage said stopfor locating the extended receptacle in the tool change position.

7. A machine tool acocrding to claim 5 including:

a source of power connected to said magazine for driving it in itsrotary movement;

reversing means responsive to the passage of the succeeding tool pastthe tool change station to reverse the direction of rotation of saidmagazine; and,

control means responsive to the passage of the selected tool past thetool change station to activate said actuating means for extending saidabutment so that during the reverse rotation of said magazine saidabutment engages said stop to terminate rotation of the magazine withthe succeeding tool located in the tool change station.

8. The machine tool according to claim 7 including:

a fixed guideway having a movable portion adjacent the tool changestation, said guideway defining a path of travel for said movable toolstorage receptacles toward and away from the tool change station andoperable to maintain said receptacles in retracted position as they aremoved to the tool change station.

9. In a machine tool:

a base;

a column mounted on said base and extending upwardly therefrom;

a tool receiving spindle journaled in said column;

a socket fixedly mounted in said column for individually receiving thetools used in said spindle, the axis of said socket being parallel tothe axis of said spindle;

a tool transfer member movably carried by said column for interchangingthe tools between said socket and said spindle; and

actuating means mounted in said column and connected to said tooltransfer member for actuating said member in its movements forperforming the tool interchange operation.

10. A machine tool according to claim 9 including:

a housing removably secured to the column in a manner to constitute anupward extension of the column and in which said socket, said tooltransfer member, and said tool transfer member actuating means, areoperatively carried.

11. A machine tool according to claim 10 in which said socket and saidtool transfer member are carried in said housing in vertical alignmentrelative to each other and also with said spindle; and,

said tool transfer member is disposed intermediate of said socket andsaid spindle.

No references cited.

RICHARD H. EANES, JR., Primary Examiner.

1. IN A MACHINE TOOL: A BASE; A COLUMN MOUNTED ON SAID BASE ANDEXTENDING UPWARDLY THEREFROM; A REMOVABLE HOUSING MOUNTED ON THE TOP OFSAID COLUMN; MEANS SECURING SAID HOUSING TO SAID COLUMN IN OPERATINGPOSITION; A TOOL RECEIVING SPINDLE JOURNALED IN SAID COLUMN; TOOLSTORAGE MEANS SUPPORTED BY SAID HOUSING FOR STORING THE TOOLS THAT ARETO BE USED IN SAID SPINDLE; A TOOL TRANSFER MEMBER MOVABLY CARRIED BYSAID HOUSING FOR INTERCHANGING TOOLS BETWEEN SAID SPINDLE AND SAIDSTORAGE MEANS; AND, ACTUATING MEANS MOUNTED IN SAID REMOVABLE HOUSINGAND CONNECTED TO SAID TOOL TRANSFER MEMBER FOR ACTUATING SAID MEMBER INITS MOVEMENTS FOR PERFORMING THE TOOL TRANSFER OPERATION.